There are a few things you can do to stop your plastic gutters from leaking. One is to make sure that they are properly fitted and sealed to your roof. Another is to keep them clean and free of debris, which will help reduce the chances of them getting clogged up and leaking. You can also use gutter guards or covers to help keep them clear and protect them from debris.

One way to stop plastic gutters from leaking is to add sealant around the joints where the gutter sections meet. Another way to stop leaks is to install gutter screens, which will keep debris out of the gutters and prevent them from clogging. If there is already a significant build-up of debris in the gutters, it may be necessary to clean them out before installing the screens.